Conventionally, polarizing plates have been widely used in liquid crystal display apparatuses, and the demand for the polarizing plates is rapidly increasing recently. Further, a polarizing plate with a high added value such as an elliptically polarizing plate provided with an optical compensation function in which at least one optical compensation layer is laminated on a polarizing plate has come into use, and there is an increasing demand for a display quality such as a high precision, high quality, and a wide viewing angle.
An optical compensation retardation film is known, in which an optical unisotropic layer containing an obliquely aligned discotic liquid crystal compound is supported by a triactate cellulose (TAC) film. Such a retardation film is directly laminated on a polarizer as a protective film having a wide viewing angle function, and is laminated on a polarizing plate to provide a wide viewing angle function (e.g., see Patent Documents 1 and 2).
However, when the above-mentioned retardation film is exposed to, for example, a high-temperature and high-humidity state, a TAC film that is a support base material may be distorted. As a result, a contract may be degraded.
Further, in the above-mentioned retardation film, an optical unisotropic layer itself is very thin, i.e., 10 μm or less, but the TAC film needs to have a thickness of about 100 μm so as to function as a support base material. Consequently, in the case of using such a retardation film, it is very difficult to make the film thin and light-weight.    Patent Document 1: JP 6-75116 A    Patent Document 2: JP 8-94838 A